Keep getting fireflies / blurry renders?

Support Lighting and Rendering
1

Hi,

I tried several options as found on the web, but I keep getting very blurry images and / or loads of white fireflies.
I model in Sketchup, import the model and add three lights. Then I place a camera, tweak the view and render (cycles). I’ve tried changing the light size. Tried clipping. Tried number of cycles. But every time the result is rather poor? I hope the settings for my rendering will be saved in the attached file so you’ll get to see what I tried.

Any help or suggestion would be greatly appreciated! I do not have to get near-realistic results, but I keep on running into this blockade?!

Details: Blender 2.78 b, Windows 10 on i5 CPU, Intel Graphics.

Attachments

Optie 1.blend (14.1 MB)

2

Hi Dutchie,

Increase number of samples. 144 is not enough. Also, using Branched Path Tracing may help a lot. Maybe try increasing number of bounces too.

3

Your clamp settings are also odd. You have Clamp Direct set to 1 - and clamp indirect set to 5.

Clamp direct should always be higher than clamp indirect and should probably be at least 10 or 15 in your scene. By setting clamp direct to 1 - you are limiting the power of all of your lamps for direct lighting. Personally I would turn clamp direct off (set it to zero) and keep clamp indirect set to 5.

Also - have you thought about lighting the exterior of your scene using a HDRI rather than the exterior point lamp. If you do this - you can use portals.

4

Hi guys, I tried, tried again but… blegh.
I followed a simple tut on here https://cgi.tutsplus.com/tutorials/create-and-render-a-still-life-scene-in-blender-using-cycles--cg-13715
but all I got was this:

render 1 fireflies.png960×540 794 KB

And these were some of the settings:

render 1 settings.png1155×1023 138 KB


One pointlight / sun outside the ‘window’, another to the top-right of the camera in order to soften the shadows and a rectangle with an emission-material (slightly yellow) for no purpose other than that it was in the tutorial :wink:

All was well untill I started adding the rectangle and light outside?? Any thoughts are appreciated!

5

That’s not a great scene for path tracers as the light source is difficult for the pathtracer to find a single small light source - outside a window.

If you lit the scene using a HDRI environment map - you could take advantage of portals.

6

Moony, Thanks, I’ll try that tomorrow (It is getting busy at work :wink: )

In the meantime, I removed all lights and got this result (I did crank up the Background| Skytexture, strength.

render 2 fireflies.png960×540 698 KB

7

optie.00.jpg960×540 50.7 KB

I set both clamps to 0.99, 30 samples (squared)

8

Your clamp settings seem awfully low.

I don’t use direct clamp settings below about 10-15 and indirect clamp below 3-5.

By clamping to 0.99 - you are losing much of the light information from your scene, especially from your direct lamps.

9

this weekend challenge “chandelier” I’ll try to use these values. thanks :slight_smile: